Copy of Upright Hammer Replacement - Piano Promo · PDF fileArticle courtesy Schaff Piano...

Schaff Piano Supply Company Presents:

Upright Hammer Replacement

By Chuck Behm

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Action / Upright Hammer Replacement

Article courtesy Schaff Piano Supply Company

-Rationale- Piano hammers are amazingly resilient, considering the fact that for the

hammers to do their job, felt is pitted against steel for decade after decade. When

a piano is new, the hammers bring out the best of the piano's potential. Over the

years, however, the integrity of the felt diminishes, and the tone of the piano suf-

fers. The useful life of a set of hammers may at times be prolonged by a profes-

sional job of shaping and voicing, but eventually wear and tear will take its toll,

and the only solution is replacement.

Piano hammers are a specialized product, and need to be duplicated to fit

the exact piano in question. Because of the amount of labor (and therefore ex-

pense) involved in the duplication and installation process, it is a procedure that

needs to be proposed thoughtfully to the owner. If the piano is indeed worth the

effort, it can make a vast improvement in the instrument. One thing to point out is

that new hammers are very long-lived, and that under normal circumstances, a

new set of hammers will most likely outlast the owner of the piano!

These instructions represent a basic starting point in learning to install ham-

mers in an upright piano. As with so many repairs, there are plenty of finer points

to be learned as one progresses in his or her development as a technician.

Upright Hammer Replacement

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Where to Begin?

When an upright piano action has deteriorated to the point where nothing

less than a complete overhaul will do, the list of things to do can seem over-

whelming. Fortunately, the job doesn't have to be done all at once, but can be

tackled one step at a time. For an action in the condition of the one used for the

photos for this article (Tryber & Sweetland, circa 1903), a good starting point

would be to have a duplicate set of hammers produced by Schaff Piano Supply

Company for replacing the old. In the case of the action shown, that repair would

be followed with a new set of bass and treble dampers, new bridle straps, new

hammer rail felt, new center pin bushings, etc., etc., etc. In addition to action

work, the piano in question was to be refinished, restrung and repinned, and out-

fitted with new keytops and key bushings.

Piano restoration is all about seeing the possibilities in an instrument that

can be brought back to life again. Nothing else in the piano repair business is as

challenging or rewarding as rejuvenating beautiful instruments from the past. For

those who haven't dabbled in restoration as of yet, this is as good of a place as any

to begin. Find an old upright, a diamond in the rough, and see what it can become

with a little elbow grease and determination.

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Before packaging up the set of hammers

to send to Schaff, clearly write your

name, along with the hammer number,

on the molding of each hammer. Use

pen, not pencil, to make sure that the

writing shows clearly. Tape the hammers

together, and include with a note listing

your business name and customer num-

ber. Box up and send to:

Schaff Piano Supply Company

attention: Hammer Duplication

451 Oakwood Road

Lake Zurich, IL 60047

Note: To facilitate the job of hammer

replacement, parts that will be in the

way of the process should be removed.

The damper assembly and damper

spring rail are obviously in the way.

Remove the dampers / damper levers

from the action.

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Number the damper heads or levers, and

store in a safe location. If a number of

actions are worked on at one time, mark

the first damper of the set with the name

of the piano the dampers go to in order

to avoid confusion.

Remove the damper spring rail. Insert

the screws into the rail so that they aren't

lost when it comes time to return the rail

to the action.

Pause:

While waiting for your new set of ham-

mers to return, use the time to begin

work on other areas needing attention.

In respect to the Tryber & Sweetland

upright featured here, the case was in

dire need of repair and refinishing. Plus,

the piano needed restringing, repinning,

new keytops, etc., etc. With a piano

restoration, there's never a lack of

projects to tackle to keep one busy

and having fun!

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Fast Forward:

Once your new set of hammers has ar-

rived, begin a new glue batch while you

take care of other preliminaries. Pour

clean water into your glue pot (Cat. No.

G-1155). Use the glue pot as a double

boiler to avoid creating a mess and save

time in cleaning up.

Now, pour a small amount of water in a

jar small enough that it will easily fit in-

side the glue pot.

Pour an appropriate amount of glue crys-

tals (dry cabinet glue: Cat. No. 399 1/2)

into the water, place jar in the glue pot,

and stir the crystals.

Note : Instructions for gluing are based

on the premise that hot hide glue is to

be used.

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Note: As long as the glue crystals are

still visible (photo), the glue is not

ready to use.

As the glue crystals begin to melt, stir

the glue and check consistency. A cor-

rectly mixed batch of hot glue will have

a consistency similar to warmed honey.

If the mix is too watery, add in more

crystals. Don't overdo this, or you will

be adding in more water.

To check the progress of your glue, lift

your brush from the glue pot, and check

to see that a long strand of glue runs off

the brush.

Caution: Your glue will stay fresh

longer if you keep it covered. If your

glue pot has a temperature control, turn

it onto the standby setting.

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Remove old unneeded hammers quickly

by splitting the moldings with a pair of

flush cutters (Cat. No. 215). First split

the molding with an up and down cut, as

shown.

For stubborn hammers, complete the re-

moval by making a side-to-side cut to

further split up the molding.

Twist hammer heads gently from side to

side, until they easily come loose with-

out damaging the hammer shank.

Caution: Don't remove the remaining

end hammer to each section, as this will

serve as your guide hammer in aligning

the new hammers for each section. Also,

a middle hammer or two for each set

might be left temporarily to check ham-

mer spacing against the strings.

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The old glue collars remain at the top of

each shank. These need to be cleaned

off.

Use a hammer shank reducer (Cat.

No.75) in tandem with a combination

handle (Cat. No. 26) to gently clean the

old glue off the shanks. Don't remove

any wood from the shanks as of yet.

Note: Guide hammers will remain for

the time being. The outside guide ham-

mers for each set will be used in lining

up the new set of hammers. Hammers

left in the center of each section will

help ascertain that the shanks are prop-

erly lined up with the strings.

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The old hammer shanks with initial

cleaning off of the old glue accom-

plished. Further work in reducing the

size of the shank may be undertaken

when the new hammers are ready to in-

stall.

Guide hammers with remaining felt need

a smooth surface. File by hand, or use a

Moto-Tool (Cat. No. D-395) for quick

results.

A smooth rounded surface is all that's

needed. The shape of the shoulders does

not matter at this point.

Note: The top guide hammer will most

likely be worn through to the wooden

molding. Don't worry about filing

smooth, as the wood marks the strike

point..

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Indicate the strike point by drawing a

line on the outer surface of the hammer

head perpendicular to the center line.

Extend the line from the reference mark

through the arrow point of the wooden

molding and on to the leading surface of

the hammer.

Remove the guide hammers one at a

time to mark the center line (which will

identify the strike point), in order to line

up the new hammers. Use a ruler (a 6"

stainless steel rule [Cat. No. 3197]would

be ideal for this) to mark the exact center

of the molding on the tail end.

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If hammer shank alignment is in ques-

tion, check it out by installing the action

in the action long enough to line up the

guide hammers with their respective sets

of strings.

Check alignment by manually pushing

up the guide hammers to the strings.

If any of the original hammer shanks are

broken or missing, this is a good time to

repair or replace. With long splits, a

splice is usually possible. For a blunt

break such as shown in the photo, re-

placement is necessary.

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For a broken stump of a shank too short

to steam and remove, snip flush with the

top of the hammer shank.

One technique for removal is to drill the

old shank out. To do this, first file off the

rough top of the remaining shank with a

flat bastard course cut file (Cat. No.

252).

To prevent the drill bit from wandering,

use an awl (Cat. No. MF-365) to mark a

center point.

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Secure the hammer butt in a drill press

vise and drill the old shank out with a

7/32" drill bit.

Replace the hammer butts due for new

upright hammer shanks (Cat. No. 504)

back into the action before installing the

new shanks.

To apply glue to a new shank, the easi-

est method is to hold the loaded glue

brush (Cat. No. 438) stationary, while

rolling the end of the shank over it.

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As the shanks are inserted into the ham-

mer butts, turn the shanks so that a glue

collar is formed.

At this point, it is time to arrange your

bench for the installation of the new

hammers. One method which will expe-

dite the process is to lay the action down

on your bench with the hammers facing

up.

The action brackets should make solid

contact with the surface of the bench.

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At the back of your bench, you may

wish to elevate the back of the action

slightly by placing wood blocks under

two or more of the action brackets.

To prevent glue from getting on the ham-

mer rail felt, use a straight edge to prop

up the hammer shanks by running it in

between the action brackets and shanks,

as shown.

Replacement shanks may now be

trimmed by using a ruler to mark the cut

line using the original shanks on either

side for the correct length.

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With any broken or missing shanks re-

paired or replaced, hammer installation

will go more smoothly than if broken

shanks need to be repaired during the

process.

Snip the ends of the new shanks off to

correct length using a pair of hammer

shank cutters (Cat. No. 237 [shown], or

Cat. No. 3208).

At this time, the new set of shanks from

Schaff should be opened.

Caution: If numerous sets of hammers

are replaced, mark the maker and

model of the piano on the outside of the

package of hammer heads to avoid a

mix-up.

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Lay out the new set of hammers on a

flat surface. The penciled in numbers put

on by Schaff correspond to the end ham-

mers from each set sent in for duplica-

tion. Hammer number 28 in the photo

corresponds to the end hammer of the

bass section, and hammer number 29

corresponds to the first hammer of the

middle section of hammers.

To avoid confusion during installation,

take the time now to number the under-

side of each hammer with the correct

number.

Note: The stamped number from the

hammer manufacturer will most likely

not correspond with the actual place-

ment number. This is because certain

hammers are removed from the new set

during the drilling process at carefully

selected places to better match the origi-

nal set of hammers.

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Reduce the size of shanks where the fit

is too tight, using your hammer shank

reducer.

Before beginning installation, check the

fit of the hammers to the shanks. Place a

hammer on each shank, and try swivel-

ing back and forth.

Note: If the hammer makes a ratcheting

noise as it is pivoted, it is way too tight.

If it squeaks or squeals as it is turned, it

is somewhat tight. It should turn freely,

but not be floppy.

Caution: Go easy. Reducing shanks is

somewhat like shortening pants—you

can always take off more material, but

it's difficult to put it back on.

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If you look inside the hammer shank

hole, you'll see an indentation from the

brad point of the drill. For the tenor and

treble hammers, center your drill bit on

that indentation and the vent hole will be

in the center of the hammer shank hole.

When the drill bit has gone through the

top of the hammer molding, hold it up to

the light to make sure that the hole is

clear.

If the set of hammers do not have pin-

prick size vent hole to prevent air bub-

bles inside the shank hole, you may wish

to consider adding them. A very fine drill

bit is needed which may be purchased at

a hobby shop. This bit, measuring .03",

is too fine for a standard drill chuck, but

may be chucked up in a pin vise (Cat.

No. 152) which in turn is put into the

chuck of a standard drill.

Note: Check the tightness of the drill bit

in the pin vise frequently, as it will tend

to loosen. When it does, the bit will slip

in the chuck,, and most likely not go

through the molding.

Caution: Keep your finger clear of the

position of the vent hole as you are

drilling. Trust me on this.

Note: The vents for bass hammers are

done differently. Directions on page 30.

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Note: If you don't wish to draw a line

along the entire side of your new ham-

mers, a simple short line at the end of

the hammer in line with the center of

the molding will do as well. Lightly

draw a perpendicular line across the

face of the hammer to indicate the strike

point line.

To hold hammers out of the way (since

the hammer shanks are in a horizontal

position), a simple tool constructed from

a short length of scrap wood, and small

eye-bolt, and a miniature bungee cord

will do the trick.

Prepare your first hammers for installa-

tion to go on either the inside or the out-

side of the guide hammers. Use the same

method as before to determine the strike

point line.

Note: Instructions are given in the order

that the photos were taken—tenor sec-

tion first, treble section second and bass

section last.

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From the opposite side of the action, this

is what the devise looks like. The bungee

cord attaches to the eye bolt which is

screwed into the piece of wood on the

front side of the shanks.

At the back of the action, attach the op-

posite end of the bungee cord to the bot-

tom of a sticker.

The short length of wood keeps hammer

shanks adjacent to the hammer / hammer

shank being worked on out of the way.

Gluing the hammer to the hammer shank

is simpler with a little elbow room, so to

speak.

Note - To move the hammer shank

clamp down the row, you'll need to dis-

connect the bungee cord from the eye-

bolt to move the block one hammer

shank over.

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With all the preparations made, and the

adjacent hammer shanks pulled back out

of the way, it's time to install the first

hammer.

Dry fit the hammer first, and make sure

there is a adequate depth to the hole so

that the strike line of the new hammer

will line up with the strike line of the

guide hammer.

If there is not enough depth for the ham-

mer to fit far enough onto the shank,

slice a sliver off the end of the shank us-

ing your hammer shank cutters rather

than drill the hole deeper. Again, go

easy. You can always slice a bit more off.

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Caution: Before using your hot glue,

double check to make sure the consis-

tency is still good. If it has been on

stand-by for some time, you may need to

mix in a bit more water. Stir, and allow

time to heat.

Using a small artist type brush dipped

into the hot glue pot, swirl the brush in

the shank hole. Don't overdo it. Too

much glue in the hole and you'll have a

mess.

Use a glue brush to dab glue onto the

end of the hammer shank. Enough so

that you'll get a nice collar, but not so

much that it's running all over.

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Lift the hammer shank, so that you're

clear of the guide hammer and put the

hammer head on the shank. To form a

nice collar, spin the hammer head com-

pletely around once or twice.

Look over the top of the hammer heads

to check the collar. (This is one advan-

tage of having the action laying on the

bench instead of standing upright.) The

collar should be neither too big or too

small.

Note: You will most likely have a bead

of glue forming at the vent hole. This is

a sign that there is adequate glue to sur-

round the shank all the way in the hole.

Wipe the bead off with a rag or paper

towel.

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Looking straight down at the guide ham-

mer and the first new hammer, the strike

lines should line up perfectly. If they

don't quite line up make a slight adjust-

ment by pushing or pulling on the tail

ever so slightly to adjust the depth of the

shank in the hole.

Use a combination square to check to

see that the new hammer is perfectly

perpendicular to the surface of the

bench.

Repeat the process with the hammer on

the opposite end of the set being worked

on, then prepare a straight edge of the

appropriate length to run from one new

hammer to the other.

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With a new hammer in place on either

side of a set, the guide hammers for that

set may now be removed. Be sure to

clean and reduce the ends of the shanks.

Starting from one direction or the other,

repeat the process for the next hammer

in. This time, instead of lining up strike

points, use your strait edge to line up the

new hammer with the two outside ham-

mers, starting with the top (or side, in

this orientation) of the molding.

Caution: Take five to give the glue on

the new hammers time to set before cut-

ting the old guide hammers off.

Caution: If you use a home made

straight-edge as shown, make sure it is

straight on all sides. Lay it on a per-

fectly flat surface, such as the bed of a

shop tool, and make sure no light is

showing underneath at any point.

Caution: If the new hammer is too far

out, push in with the straight edge, but

stay below the vent hole to avoid mak-

ing a mess. Glue should squeeze out of

the vent if you're using enough glue.

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If the hammer is too far in, grasp the

molding as shown in the photo (see here

a bit further down the line), and gently

pull the hammer out to the straight edge.

Keep your thumb on the straight edge

and pull with your second and third fin-

ger on either side of the shank.

Next, check the profile of the felt at the

outermost point on the opposite side of

the hammers.

If there is a bit of misalignment, gently

tip the head one way or the other as

shown to bring the hammer head in line.

Caution: Avoid placing your fingers so

close to the shank that they're in the

glue collar..

Caution: At this point, avoid pulling

the hammer in or out on the shank.

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Keeping your straight edge moving,

quickly check the opposite side of the

felt.

Quickly check the to see that the ham-

mer is perpendicular. If hammer is tilted,

rotate until it lines up with the square.

Again, if an adjustment is made here, go

back and double check the other adjust-

ments. Repeat until everything lines up.

Note: As you move down the line, keep

moving your hammer shank clamp one

step ahead of where you're at. Keeping

the road clear on one side makes it eas-

ier to spin each hammer head to form

the collar.

Caution: If you've tipped the hammer

head slightly to achieve alignment of

the felt, quickly double check the align-

ment of the wooden molding, to make

sure the hammer hasn't been pulled out

or pushed in on the shank.

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As you work, pay attention to the details.

Make sure that your collars are evenly

formed.

Clean vent holes as you go. When the

glue is firmly set, lightly go over the

tops of the molding with 220 grit sand-

paper if they need further cleaning.

With the tenor and treble sections of the

action completed, installation of bass

hammers will finish the job. To align ref-

erence hammers, adjust position using

the edge of the strike lines.

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For bass hammers with a slanted bore

hole locating the vent holes in the center

of the molding requires a different start

point for your drill if you wish the hole

to be centered topside. Instead of lining

up your bit with the center of the ham-

mer shank hole, locate it along the edge

of the hole, as shown.

Note: Comparison between vent hole

drilled using the center of the shank

hole as the starting point, vs. drilling the

vent off to the edge of the shank hole.

Remove the original guide hammers, and

use hammer shank clamp to clear your

path for gluing.

Edge of

shank hole

Center of

shank hole

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For the bass hammers, follow the same

gluing procedures as with the tenor and

treble. Start alignment by using straight-

edge to line up the edge of the molding

of the new hammer with that of the ref-

erence hammers on either end.

Next, check to see that the hammer is

perpendicular by holding your combina-

tion square at a right angle to the center

of the molding. Check this before you

check the hammer felt for alignment.

Use the corner of your straightedge to

check the alignment of the hammer felt

of the hammer being glued to the refer-

ence hammers on either end. If it's

slightly off, tip the hammerhead a bit to

bring the hammer into alignment.

Hint: If you turn your straightedge

slightly so that the corner of the

straightedge is touching the edge of the

hammer molding it's easier to see any

gaps in between the hammer and

straightedge.

Caution: It's important to go through

these steps a second time to make sure

that everything is correct before the

glue begins to set.

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Tools and Supplies For your convenience, all the tools and supplies necessary to

complete a hammer replacement job are listed with correspond-

ing catalogue number.

Tools: Glue pot..............................................................Cat. No. G-1155

Flush cutters.............................................................Cat. No. 215

Hammer shank reducer ..............................................Cat. No.75

Combination handle...................................................Cat. No. 26

Moto-Tool............................................................Cat. No. D-395

6" stainless steel rule..............................................Cat. No. 3197

Flat bastard course cut file.......................................Cat. No. 252

Awl....................................................................Cat. No. MF-365

Glue brushes (12).....................................................Cat. No. 438

Hammer shank cutters..................Cat. No. 237 or Cat. No. 3208

Pin vise.....................................................................Cat. No. 152

Supplies: Dry cabinet glue................................................Cat. No. 399 1/2

Upright hammer shanks...........................................Cat. No. 504

To order, call Schaff Piano Supply at 1-800-747-4266 or visit on the web at www.schaffpiano.com

Important note: Ordering information is given

for the use of Schaff account holders only.

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Afterword: Moving Towards the Realm of a Full-Service Shop

The benefits of maintaining a shop (which might be as small as a dedicated

bench in the basement, or as large as an entire barn building—I've seen both ends

of the spectrum) in conjunction with a piano tuning / repair business are many, es-

pecially when one begins to move into repairs which belong in the realm of the

full-service shop. Offering hammer replacement services is a good example of the

type of repair which will set your shop apart from those who don't offer a full

range of repairs options to their piano customers.

First of all, for the technician who would like more business coming in to

help the bottom line, nothing is better for one's reputation as being a serviceman /

woman who can "do it all." When word begins to get around that no matter what

the problem with a piano, you're the guy to call, you will see your calendar begin

to fill up with appointments and projects. Offering complete action repair service

(being able to take the action shown on page 3 of this article, and transform it into

the action in the above photo, for example) is one step to becoming a full-service

shop that customers will turn to in confidence that the job will not only be done,

but be done right.

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When one offers a full range of repair services, each piano looked over for

the first time offers enhanced opportunities. Instead of examining a down-and-out

instrument that has been neglected for years and declaring it to be "beyond hope,"

the skilled technician can see in his / her eyes what's possible, and can share that

vision with the owner. Obviously, not every piano should be restored to the full-

est extent possible, but many instruments (especially vintage, pre-WW II instru-

ments) have the potential to be given an amazing second life. With the facilities

and the skills to do the jobs that need to be done, a piano that has limped along

with mediocre service for years can be turned into a jewel of an instrument. When

this happens, not only does the piano shine again—so does your reputation!

Having a busy shop not only is helpful to the technician's bottom line, but it

is a godsend for one's mental being. As one who's done the 30 - 40 tunings a week

grind for weeks on end, I know that scheduling time in the shop on a regular basis

is the tonic for avoiding burn-out. A day or two in the shop does wonders for one's

frame of mind.

Having project pi-

anos torn apart

and awaiting your

touch gives pur-

pose to your days,

and keeps the

juices flowing. At

any one time, we

average three pi-

anos in various

stages of restora-

tion, so when I go

out to the shop in

the morning, I

know that I can

take my pick of

projects to tackle.

When days which are filled with tuning appointments roll around, it's a good feel-

ing to gas up the car and get out on the road again. Variety, as they say, is truly the

spice of life.

Having a fully equipped shop is also a great way to retire from a full-time

piano tuning business, when one gets to the point where hitting the road has little

appeal. One can make the transition gradually, if needs be, referring tuning cus-

tomers a few at a time to trusted area tuners, while maintaining those contacts

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which one has serviced the longest (or enjoys the most) until the time comes to

part with those as well. Even without a regular tuning schedule, the skilled techni-

cian / shop owner can bring in shop work by putting out the word to local tuners

that you're available for the doing the repair work they may not have time for.

Retiring from the tuning end of the business does not necessitate retiring from the

piano repair business altogether. Having a shop to go out to work in beats sitting

around watching the tube!

Where to begin? Start by keeping an eye out for opportunities to offer your

services. When a piano comes along that seems to hold potential for improve-

ment, think big, and don't be put off by a real challenge (see photo). Give a full-

blown estimate of all the repairs which you are capable of providing, and be will-

ing to explain what exactly those repairs will entail. I find it best to give an item-

ized list of repairs, along with prices, so that the customer is empowered to decide

which exact repairs to leave in and which repairs to leave out. Oftentimes, when

everything is explained, and the customer

has had a chance to think things over, own-

ers who want to see their piano brought back

to life will frequently request to do the entire

package. Sometimes the only question the

owner has is, "When can you work it in?"

Those words are music to my ears!

For a vintage upright piano (such as

the one featured in this article) I always take

pains to explain that the commercial value of

the instrument will most likely be less than

the repair bill (sometimes far less), but that

in terms of playability many old uprights are

wonderful instruments, once they have been

returned to more of what they were like

when they were new. The other factor to be

considered, of course, is sentimental value.

If the piano belonged to the mother or grand-

mother of the current owner, commercial

value is typically a moot point. It's never going to be for sale, anyway.

If you're a good salesman, and do good work, you will soon find yourself

with a waiting list of customers eager for your services. Nothing beats knowing

that you have the next 5 or 6 jobs booked, and ready to be delivered to your shop!

Chuck Behm

Tryber & Sweetland's case detail.

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Tryber & Sweetland's case—after

Tryber & Sweetland's case—befoe

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Notes on Procedures

Copy of Upright Hammer Replacement - Piano Promo · PDF fileArticle courtesy Schaff Piano...

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Transcript of Copy of Upright Hammer Replacement - Piano Promo · PDF fileArticle courtesy Schaff Piano...